Google alert precise that on 24 December they detected and blocked an unauthorized digital certificate for the “*.google.com” domain. This certificat was issued by an intermediate certificate authority (CA) linked to TURKTRUST. After investigation, in collaboration with TURKTRUST, it appears that an additional intermediate certificate authority was also compromised. Google Chrome certificate revocation list has been updated the 26 December to block these fraudulent intermediate CA.

Microsoft has release an Security Advisory MSA-2798897, who affects all supported releases of Microsoft Windows. Microsoft is updating the Certificate Trust list and provide an update for all supported releases of Microsoft Windows that removes these fraudulent certificates. Systems using Windows 8, Windows RT, Windows Server 2012, and devices running Windows Phone 8 are automatically updated and protected.

The following certificates will be added to the Untrusted Certificates folder:

Mozilla has release a Security Blog Post and take a different position than Google or Microsoft. The foundation will actively revoke trust for the two fraudulent certificates, but also suspend inclusion of the “TÜRKTRUST Bilgi ?leti?im ve Bili?im Güvenli?i Hizmetleri A.?. (c) Aral?k 2007” root certificate, pending further review. A new release of Firefox will be released on Tuesday 8th January.

These fraudulent certificate could be used to spoof content, perform phishing attacks, or perform man-in-the-middle attacks, so we advise you to update asap.